Given that our last measurement was at the beginning of August, and the site is now well beyond 200M, that means that Instagram added some 50 million photos in August alone.

In keeping with our previous Flickr comparisons, that’s 200 million photos for the 10-month old Instagram, when it took Flickr almost 2 years to reach 100 million photos. Still, that’s a bit of an apples and oranges comparison, isn’t it? After all, Flickr reached its 100 millionth photo back in February 2006. The iPhone itself wasn’t unveiled until June 2007. And even then, it was nowhere near as ubiquitous a device as it is today.

Facebook plans to add a series of photo filters to its mobile application in the coming months with the hopes of drawing off fans of Instagram, the popular photo-sharing application.

The new feature has been ready for some time, according to two engineers who work at Facebook, but Mark Zuckerberg, Facebook’s chief executive, hopes his engineers and artists create more filters before releasing the new product. Both Facebook engineers asked not to be named as they are not allowed to speak publicly for the company about unannounced products.

The engineers said Facebook will introduce almost a dozen photo filters, including some that are similar to Instagram like old-style camera lenses and grainy film. Facebook will also try to introduce new styles of filters with the hopes of drawing users away from other photo apps.

The engineers also said that Facebook attempted to acquire Instagram over the summer, but to no avail.

Kevin Systrom, co-founder of Instagram, declined to comment about acquisitions or Facebook’s plans to release competing software. Facebook did not respond to a request for comment.

Facebook might have more competition to worry about than just Instagram. Programming code found in the upcoming release of Apple’s iOS 5 shows a series of new photo filters that are likely to be integrated directly into Apple’s mobile platform, MG Siegler of the blog TechCrunch noted earlier this month.

Instagram has grown voraciously since its debut less than a year ago. The company now boasts more than eight million users. In February Instagramraised a $7 million round in funding led by Benchmark Capital.